classmates = ['Michael', 'Bob', 'Tracy']
print(classmates)
print("classmates lenght is :%d" % len(classmates))

classmates.append('Adam')
print(classmates)
classmates.insert(1, 'Jack')
print(classmates)
classmates.pop()
print(classmates)
classmates.pop(1)
print(classmates)


#==========================

L = ['Apple', 123, True]
print(L)
s = ['python', 'java', ['asp', 'php'], 'scheme']
print(s)

#==========================

print('==========================')

## tuple 和list非常类似，但是tuple一旦初始化就不能修改，比如同样是列出同学的名字：

classmates = ('Michael', 'Bob', 'Tracy')
print(classmates)